基于抛物方程的短波电离层传播数值模拟研究

短波电离层传播损耗的计算对电离层基础研究与短波通信、天波超视距雷达等应用有重要意义,以往主要采用半经验模型.文中基于电磁波传播的抛物方程方法,实现对短波电离层传播损耗空间分布的数值计算,该方法可同时考虑电磁波传播的折射、反射、绕射和吸收等效应.根据电子浓度剖面数据,仿真计算了不同频点和天线波束宽度情况下的电离层传播损耗,从折射效应引起的传播模式、反射点高度、地面落区位置方面,与射线描迹结果进行对比,两者具有一致性.此外,进一步仿真分析了电离层的吸收效应.研究结果初步表明了抛物方程方法预测电离层传播的有效性及其强大的功能.

Numerical simulation of ionospheric propagation loss at HF based on parabolic equation

The calculations of ionosphere propagation loss have important meaning for fundamental research of ionosphere and applications of HF communication or over-the-horizon radar, which are usually adopted by semi-empirical model. The parabolic equation methods for electromagnetic wave propagation are proposed to numerically calculate the space distribution of path loss affected by ionosphere at HF. The numerical techniques can consider effects of refraction, reflection, diffraction and absorption of ionospheric propagation simultaneously. Propagation loss is simulated under different frequency and beam width using a profile of electron concentration. The propagation mode, reflection height and situation are compared with the results from ray tracing, demonstrating that they are consistent with each other. Absorption effects for ionosphere are simulated and used to analyze by the numerical method. The study preliminarily shows the validity of the powerful numerical techniques of parabolic equation methods for assessing ionospheric propagation.